Done fermenting in 4 days?

[jeffmesa369]

I recently set batch to ferment with US-05 and my airlock activity stopped at 4 days. It is a relatively small beer, as it only has ~3lb dme to 4.5 gallons. I am unsure if it is done or stopped because the yeast I used had a best by date that was up this month. I did have vigorous activity for 2-3 days, and the activity stopped. Coincidentally, the temp dropped to 57 degrees when activity stopped. Unfortunately, I didnt take a OG reading but it is currently at 1.012 and i cant taste any sugars, but i have a novice pallate. What say you?

 

[Psylocide]

I say give it at least another week. Your OG was only ~1.030, so 1.012 may not be quite done, but it could be. Initial fermentation doesn't last long, but that doesn't mean the yeast aren't still working.

You've got a ~2.4% beer on your hands right now.

 

[TheCADJockey]

Airlock activity doesn't mean much. Even if it stops bubbling the yeast can still be working away. Give it some time, be patient. If you absolutely can't wait, check it again in a couple days. If you think it got too cold move it somewhere a little warmer for a few days. US-05 is a pretty tough yeast for me though, it's seen some cold temps but I keep it in a swamp-cooler at 61 degrees for a few weeks then let it warm up to room temp.

 

[kh54s10]

Your dme to water only started at about 1.029 so it might be done. But,at 59 degrees the yeast may have gone dormant. Warm it up and see if it starts again
Even if done fermenting that doesn't mean that it is ready. With only dme and that low of an OG it is not surprising that you have a weak thin beer. Give it 10-14 days then bottle it, condition at about 70 degrees for 3 weeks. It will taste different when done.

 

[Yooper]

Yes, that would be expected. Active fermentation is generally over in 3-5 days in a beer that is not a very high OG, but it may continue a tiny bit longer to get the last bit done. At this point, for the first 24 hours or so after fermentation winds down, the yeast go back and 'clean up'. Once the fermentable sugars are gone, the yeast will continue to digest things like their own waste products like diacetyl before becoming dormant. Then the beer will start to clear.

That's the reason that most people will leave their beer in the fermenter for a while after fermentation ends- for the yeast to finish their job and for the beer to clear a bit. I generally package the beer when the beer is clear, and has been at the FG for at least three days (sometimes quite a bit longer, if the yeast takes a bit longer to clear).

 

[trentm]

Yes, that would be expected. Active fermentation is generally over in 3-5 days in a beer that is not a very high OG, but it may continue a tiny bit longer to get the last bit done. At this point, for the first 24 hours or so after fermentation winds down, the yeast go back and 'clean up'. Once the fermentable sugars are gone, the yeast will continue to digest things like their own waste products like diacetyl before becoming dormant. Then the beer will start to clear.

That's the reason that most people will leave their beer in the fermenter for a while after fermentation ends- for the yeast to finish their job and for the beer to clear a bit. I generally package the beer when the beer is clear, and has been at the FG for at least three days (sometimes quite a bit longer, if the yeast takes a bit longer to clear).

It seems all of the above is good advice. Just a comment on your airlock activity. As your fermentation slowed the heat from the fermentation reduced as well, thus the temperature drop. As the temperature of a liquid drops it's ability to hold gas (CO2 in the case) increases. So some of the CO2 being generated by the yeast is being absorbed into the soon to be beer. All is good.

Note: I believe there is an benefit in keeping the temperature of a fermentation constant or increasing throughout the fermentation. So after the fermentation peaks, I begin increasing the ambient temperature in an effort to keep the fermentation from cooling or on a slight daily increase.

 

[bragona71]

I just found this link on another thread its a good read check it out

PROPS to who originally posted it (I couldn't find thread again)

http://www.brewgeeks.com/the-life-cycle-of-yeast.html

 

[jeffmesa369]

Thanks folks for the info! It was very helpful.

 

[Talgrath]

One thing to note is that just because you aren't seeing the gasses escape, doesn't mean they aren't. The bubbles could be happening in terms of hours apart, or the amount being released is small enough to not be noticeable. As others have stated, airlock activity is not a great indicator that a beer is done. Personally, I let every beer ferment at least 1 week before I start testing the FG, for the vast majority (aside from my low OG beers) I let them sit 2 weeks.